Brake



Patented Jan. 22, 1929.

UNITED STATES 1,699,339 PATENT OFFICE.

HOWARD M. LEONARD, OF SOUTH BEND, INDIANA, ASSIGNOR T BENDIX BRAKE COM#`A PANY, OF CHICAGO, ILLINOIS,

A CORPORATION or ILLINOIS.

BRAKE.

l.ippimimion ined March 7, 1927. serial No. 173,245.

This invention relates to brakes, and is illustrated as embodiedin aninternal expanding brake of the type having three floating shoesarranged end to end Within the drum.

Various features 0f novelty relate to applying means including a pair oflevers aet Y ing on two of the shoes (or on equivalent friction means)and one of which operates a third lever, to novel torque-taking devicesarranged to wedge the shoes against the drum, to a new form of applyingor expanding cam, and to other novel and desirable particularconstructions which will be apparent fr om the followingdescription ofthe illustrative embodiment shown in the accompanying drawing, inwhich:y

Figure l is a vertical section through the i brake, just inside the headofthe brake drum, and showing the brake shoes in side elevation;

- and Figure 2 is a partial sectionon the line 2-2 of Figure 1, showingthe' spring arrangement.

The brake includes generally a rotatable drum 10, atthe open side ofwhich is the lusual backing plate or other support 12, and within whichis arranged the friction means, which is shown as including threelfloating interchangeable shoes 14, 1 6, and 18, each approximately 120Oin length, arranged end to end.

At each end of cacltshoe is a double-wedge recess 20 facing toward ithecenter of the drum, and within each're'cess there is a part such aroller 22 -iiiounted 0n the backing plate 12. Rollers22-have threefunctions.: (1) they positionthe shoes when the brake is released; theytalie the braking torque; and (3) t ey wedge-the shoes against the drumas they tend to turn with the drum' when the brake is applied. p

A- spring 24 is .connected directly at its right end to the lower end ofshoe 14 and by a clip 26 slidable on its end it supports the righteiidof shoe 16,-i. e. outward movement of shoe 16 acts through clifp 26to distort spring 24 crosswise. At its le t end, spring 24 is directlyconnected to the lower end of shoe 18, and a second clip 28 serves tosupport the left end of shoe 16. A second spring 30 is directlyconnected at its lower end to the left end of shoe 16, while its upperend is connected directly to the upper end of shoe 18, and by a clip 32is also-connected to the upper end of shoe 14. i

Shoe 14 is applied by a lever 34 mounted the terms of the 'appendedclaims.

at its lower end on a pivot 36 carried by backing plate 12, andpreferably having a roller or other part 38 having rolling engagementwith the shoe approximately at its cen It will be seen that all threeshoes are ap` y plied by forcing apart the upper ends of thev pair oflevers 34 and 40. For' this purpose s I provide a novel cam orexpanding' device.

54, integral with or secured to the usual camshaft. This device has oneprojection 56 extending betwecn the ends of the levers and serving acani acting on lever 40 to apply shoe 18 (and 16),.and a secondprojection 58 on the opposite side of the end of lever 34 and serving asa cani acting on that lever to apply shoe 14. The two projections definea notch receiving the end of lever 34 l/Vhile oneillustrative embodimenthas been described in detail, it is not my intention to limit the scopeof the invention to that particular embodiment, or otherwise than by lclaiiji'i: ,l 1. A brake coniprisii'ig, in combination, a drum, at leastthree ,shoes' arranged end to end within the-druin, a pair of leversarranged to be forced apart to apply two ofthe shoes,

and a third lever operated by one of said pair 9 olf levers and arrangedto apply thethird s oe.

2. A brake comprising, in combination, a drum, at least three shoes.arranged end to end within the drum,.a pair of levers pivoted near theirends and arranged to be forced apart to apply two ofthe shoes and one ofwhich has a part extending beyond its pivot, and a third lever operatedby said-part and arranged to-apply the third shoe. l

lflO

3. A brake comprising, in combination, a A

drum, at least three shoes arranged end to end within the drum', a pairof levers pivoted Inear their ends and arranged to be forced apart toapply two of the shoes and one of 'relie-h has apart extending fengagingsaidxpart at one end andthe third slioe at the'other end.

4, A brake comprising, in combination, a.

drum, friction means-engageable with .the drum, al air of levers havingrollers between their en -s which act on the friction means, a thirdlever operatively engaged by one of the pair of levers and which alsohas a roller acting on the friction means, and means :tor forcingthe'pairo levers in opposite directions to cause the three rollers toforce the friction means against the drum.

5. A brake comprising, in combination.4 a drum, friction meansengagcable with the drum, a pair of levers having parts'which act onthefrictionmeans, a third lever operatively enga ed by o'rieo'f the pair oflevers and which also has'a'part acting on the friction means, andmeansy for forcing the pair of levers in opposite directions to causethe three said parts to force the friction means against the drum.

6. A brake comprising, in combination, a drum, a lurality of unconnectedfloating segmental s oes arranged end to end within the drum and'eaclnof which has at each end a Abraking torque? duble-wedge recessfacing toward the center of the drum, agpaa-t ineach recess to take thedat `the'sam'e time to Wedge l the shoe againsti'tl-ie drum, and acorresponding plurality'ofifinterconnected levers acting on thethreefshoes approximately at their centers toforce th'em against thedrum;

.7. Brake-applying meansfcomprising, iin combination, a pair of pivotedparts having their free ends adjacent each other, anda rotatableapplying device between said ends having a projection extending betweensaid ends and serving' as a cam acting one one of said ends and having asecond projection on the opposite side of the other of said ends andacting as a cani thercagainst, the two projections defining a notch inwhich said other at least one of theother levers being"arrangeq.k K

to be operated solely by saidone oftlie levers:

9. Brake-applying means for a bralrelh'zw-L ing' a drum, comprlsing aAlever arralng'ebl",-

fulcrnn'ied between its within the drinn and ends, operating incanSatone end of said lever,

a brake-ap lying'tpart between said means and the fu cruinr of thelever, `and another lever having another brake-applying part 'and whichis operated by thelirst lever..

in combination,

10. A brake comprising, a drum, a plurali'tyof unconnected floatingsegmental shoes arranged end to end Within the drum, and a plurality ofoperating devi ces, one for each shoe, at least one of which, l

devices is'operated solely by one of the other devices. 'v'

11. A brake comprising, in combination, a drum, a plurality of shoesarranged end to end within the drum', and a plurality of operatingdevices' one for each shoe, at least one of which devices is operatedsolely by one of the other devices. y K p .In testimony -whereof, I havehereunto signed my name.

HOWARD 1st-LEONARD;

